Shield Splitter acceleration penalty

Hi all.

Not sure if this the correct place to ask for calculations, but I am curious.


Been trying to cook up a build for my ship, which led to me using Shield Splitter.


It says a penalty of -39.4% acceleration.

my ship, at max rank, has an acceleration of 102 (90 base + 12 from level).


When equipped with shield splitter, it drops down to 59. This is really bizarre. 


Most other stuff in this game are based on the base value at level 1, then adding the level bonus last. So going by that logic, it would be 90*(1-39.4%)+12 = 66.54 acceleration rather than 59.


The above rule works for Tetraoxide Injector which INCREASES acceleration, but once a DECREASE is introduced, the math gets weird.


Another thought is “what if the level bonus is a percentage as well?”. Going by that, 12/90 = 2/15. 90*(1+2/15-39.4%) = 66.54, nope not this either. 


A percentage increase in final value? 90*(1-39.4%)*(1+2/15) = 61.812, no.


I even considered “time taken to accelerate”. At a speed of 293, 102 accel would take 2.87seconds to go from 0 to full. 2.87*(1+0.394) = 4.00, 293/4 = 73.25, no.


I am pretty sure it shouldn’t be the simple 1-39.4%, because that would mean with 3 shield splitters, the acceleration will be less than 0, hence impossible.


But I just really cannot figure out how this penalty is supposed to be calculated.


Please help